1. Field of the Invention
The present invention relates to an air relief valve and, in particular, to an air relief valve structure of a pressure cooker that allows food materials to be discharged from an air relief hole to prevent the food material from clogging the pressure cooker and reducing the relief pressure of the pressure cooker.
2. Description of the Prior Art
As civilization, science and technology advance, various modern products are introduced into our life. As to dining, people cooked rice and food by burning wood in the past, and started using products such as electronic cookers or electric cookers after electricity and gas are invented or discovered. However, some still use gas for cooking rice or other food. However, the oil price keeps increasing recently, and the price of some of the daily necessary materials also increases. Of course, these daily necessary materials also include the indispensable resources or energies such as water, electricity and gas. When the aforementioned resources or energies are used, the power saving issue is also taken into consideration to save costs and family expenses. In the age of an increased price of daily necessities and energies, related manufacturers spare no effort to develop products with the features of power saving and carbon reduction and of overcoming environmental issues. Among the aforementioned cooking devices, the electric cookers and electronic cookers for cooking food and rice are necessary electric appliances. The longer the cooking time, the greater the energy consumption. Therefore, it is a main subject for related manufacturers to develop a cooking device that can cook food or rice quickly.
Pressure cookers available in the market can overcome the aforementioned problem. The basic structure of a general pressure cooker includes a steel airtight container combined with a pressure relief valve. At a higher pressure, the boiling point of liquid increases. Based on this physical phenomenon, the pressure cooker can apply pressure to water, such that the water can reach a higher temperature without boiling to expedite the cooking of food, to achieve the effect of saving time and energy.
However, most conventional pressure relief valves used in a pressure cooker can be used simply for discharging gas to reduce the pressure in the pressure cooker. If the air relief hole is clogged by food materials, then, the purpose of relieving pressure cannot be achieved quickly and effectively. The pressure relief valve fails to discharge gas quickly and effectively mainly due to the too-small air relief hole. As a result, a small amount of food debris may occupy the whole pressure relief space easily and cause the failure of relieving the pressure.